Amsterdam placental workshop group consensus on staging and grading of maternal and fetal inflammatory responses
Inflammatory response | |||
Maternal | Fetal | ||
Stage | 1 Early | Acute subchorionitis or chorionitis | Chorionic vasculitis or umbilical phlebitis |
2 Intermediate | Acute chorioamnionitis | Umbilical vasculitis (one or both arteries with or without vein) or umbilical panvasculitis (all three vessels) | |
3 Advanced | Necrotising chorioamnionitis | Necrotising funisitis or concentric umbilical perivasculitis | |
Grade | 1 Mild–moderate | No specific terminology/not severe | No specific terminology/not severe |
2 Severe | Acute chorioamnionitis, subchorionic abscesses | Intense chorionic/umbilical vasculitis | |
Other | Chronic or subacute chorioamnionitis | Associated fetal thrombi Peripheral funisitis Acute villitis Acute intervillositis with intervillous abscesses Decidual plasma cells |
Adapted from: Redline et al 92 and Khong et al. 30